[ICOM] IC-751A Transmit Problem

[Ed Myers]

SYMPTOMS: 

Receive function is normal at all times

Transmit function fails after a few hours or it may continue to operate for
a few days, then.

Activating the transmit function switches off the receive function but the
xmit function fails.

 

I have not opened up the rig yet but do have a Service Manual. The R/T
function is complex

because there are different times associated with the various modes. This
rig has been on-line 

for several years on a PACKET 24/7 BBS. It does not seem heat related
because the failures 

have occurred a few minutes after the rig is turned on from a cold start.
The failures also occur when

the PA has not been activated prior to the failure.

 

I would appreciate any hints before I proceed.

 

Ed        WC4TT